Buffalo Turkey Sandwich

In a bowl, whisk together sour cream, lemon juice, sugar, kosher salt, and pepper. Fold in shredded iceberg lettuce, scallions, and crumbled blue cheese. In a small skillet, whisk together Buffalo wing sauce and water. Add shredded turkey and cook over medium heat until heated through. Form sandwiches with bread rolls, the turkey mixture, and the blue cheese salad.